Radio alarm transmitting, recording, and signaling system



1 1951 P. E. FISCHLER 2,574,696

RADIO ALARM TRANSMITTING RECORDING AND SIGNALING SYSTEM Filed March 5,19 19 2 SHEETS-SHEET l INVEN TOR. RAUL E. FISCHLER ATTORNEYS.

Nov. 13, 1951 P. E. FISCHLER 2,574,696

RADIO ALARM TRANSMITTING RECORDING AND SIGNALING SYSTEM Filed Marh :5, 149 2 SHEETSSHEET 2 ATTORNEYS.

m mL H mm. l lm mm k W exbYnEWQ E l l I I I I I I I I l I I IJ L m u 3 MP l I I l l |lJ|1||||||. Y O B l PI I l I I l v 1 am 9: wot @whfi L rPatented Nov. 13, 1951 OFFICE RADIO ALARM TRANSMITTING, RECORD- ING, ANDSIGNALING SYSTEM Paul E. Fischler, Bufialo, N. Y., assignor of onehalfto John Nathanson, Buffalo, N. Y.

Application March 3, 1949, Serial No. 79,323

This invention relates to a radio alarm transmitting, recording, andsignalling system and may be used wherever such systems are necessary ordesirable.

It is particularly well adapted for use as a fire alarm system, and byway of illustration, it will be described in connection with suchsystems, although its use is not limited thereto.

In rural or suburban areas the fire alarm systems are generallyinadequate or non-existent because of the poles and wires necessary withan adequate number of pull boxes, and the cost of known systems isusually beyond the means of small communities and the maintenance ofwired systems is comparatively high because of the exposed wire plant.

Most communities are dependent upon the telephone to notify the firehouse in time of fire and the time lost between the discovery of a fireand the notification of the fire company and the assembling of' men andapparatus at the scene of the fire is often considerable.

The system herein described has for its object the solution of theforegoing and other problems commonly met with in connection with firealarm systems, as by the use of the present system, the signals aretransmitted from the pull boxes to the fire house in which the'receiveris located without the use of wires and the pull boxes, when operated,automatically transmit impulses and put into operation a fire alarmwhich will be broadcast by a siren at the fire house or wherever thereceiver is located, said broadcast to be followed by a coded air hornsignal by which all those within hearing can determine which pull box isoperated. These signals may be repeated any number of times.

An object of the invention is to provide a transmitter pull-box having aspring motor controlled by a manually operable lever, which whenreleased, will cause the device to automatically release a series ofsignal pulses automatically repeated any desired number of times. Thiseliminates such difliculties as occur from the use of telephone dialswitches or the like, which must be correctly manipulated by the user ora wrong signal will result.

Another object of the invention is to provide a transmitter pull-boxwhich is automatically resetting after use. 1

Another object is to provide an audio impulse recording device in whichall stepper relays and selector switches are eliminated and in which theincoming signals from the pull-boxes are recorded on a tape, which inturn operates signalling devices such as a sirenv and air horn.

11 Claims. (Cl. 177-354) A further object is to provide a signallingdevice in which incoming signals from any number of pull boxes may bestored on the tape at one minute'intervals, the signalling mechanismbeing automatically maintained in operation until all stored signalshave been coded by the air horn.

In the accompanying drawings:

Figure 1 is a diagram of the audio impluse coding mechanism for use at apull-box used with the alarm system embodying the invention;

Figure 2 is a sectional view on the line 2, 2 of Figure 1;

Figure 3 is aside view of the door l5 of the cast aluminum housing 62(Figure 5) showing the actuating lever l4 supported thereon.

Figure 4 is a diagram of the audio impulserecording and signallingdevice operated by the pull boxes shown in the preceding figures; and

Figure 5 is a diagram of the apparatus shown in the preceding figuresconnected to form the complete radio alarm transmitting, recording andsignalling system herein described.

Audio impulse coding mechanism for radio alarm pull-box This mechanism,driven by a spring motor, is used to control the operation of a radiotransmitter, modulated with a selected audible tone in the frequencyspectrum between and 8,000 O. P. S. modulation occurring as a series ofpulses so spaced as to indicate the number of the pull-box.

The National Board of Fire Underwriters requirements state that no boxnumber shall be composed of more than three digits, and that thesedigits must be repeated four times when sounding an alarm. The codingmechanism to be described was designed, therefore, to code any boxnumber from 2 to 999, andto repeat the digits four times. Numbers 1, 10,11, 20, 30, etc. are omitted as they cannot be clearly coded.

For accuracy of transmission, the pulse speed is set at three persecond, with intervals of one second between digits and two secondsbetween groups of digits. Since 999 is the highest number to be cod-ed,50 seconds are required to transmit this number four times.

A mounting plate In carries the spring motor [0a which is connected toshaft I I through gear Ha to drive discs l2 and I3 at 1 R. P. M. Whenthe actuating lever l4 mounted on door I5 is depressed, the cam IE onsaid lever engages the hinged latch bar I! at point I8, closing thecontacts I 9, 20 to energize the transmitter tube filaments hereinafterreferredta...

This action also raises the opposite end of the latch bar out of slot 2|in disc l2, allowing discs 12 and I3 to rotate. The latch bar I! rideson the face of the disc l2 during rotation, thereby maintaining contactsI9, closed. The actuating lever l4 returns to its normal position byreasonmftthe pressure of spring '22.

The transmitted tube iilamentsare allowed to reach normal operatingtemperature during the first 10 seconds of disc rotation by reason ofthe cut-away portion 23 on disc l3. ..Coding.teeth-2.4 on the disc l3are then in positiontoactuatenontacts 25, 26 which close a circuitcausing the audio oscillator to modulate thettransmrttenwith pulsesdesignating the pull-box number all as presently described.

Upon completion of one revolution of 'discs l2, l3, the latch bar Hunder pressure of =spring'21 falls back into slot 2| stopping the motor.This action :alsoiopens aiilament contacts 1 I-9, .20. lFhe mechanism:ismownutomaticallyreset :for subsequent operation.

:In practice, .thie .rlisc 1:3 15.;f8blifi8it6d with teeth equally.spaced around ithe-zentire circumference .and it fis :wthenlsmilled :toremove ithose teeth not required.

Audio impulse :recor'cling and signaling device This .device;-.isdesigned'to operate from the output of :a suitablevreceiver:-as.shown in.E'ig. 5 to record coded audio signals from the pull-boxes shown inFigs. lito .3 inclusive, and .to employ these. recorded .signalstoautomatically .operatea warning -siren followed by; air-horn signals.designating the -.number .of ,pull-box. .Reference is now made -.toBig. ,4

.Standard-type-paper tape..28,is .stored on the reel .29 .and.threadedthrtmgh guide wheels .30, 3| lover drive .disc 32, throughguide wheels33, 34, and .over. .disc. 3.5.

Drive disc.;32ihas.aldiameter .of 2 inches and is geared to synchronousmotor 36 to rotate in a clockwise direction .at a :speed .of 4 R..P. M.Therefore, 31.4 inches of-tape-pass over this disc per minute. Since itrequires 50 seconds for the highest pull-box number, '9'99,-=to betransmitted and received, 262- incheso'f -tape will be'employed inrecording these signals, 'and the remaining 5.2"in-ches is'requiredtospan the distance between perforating punch '31 and-signaling contacts38 and 39.

Drive disc 35 also has a diameter of 2%i-nches and is eared tosynchronous =motor 40 to rotate in a-clockwisedirection'at aspeed'o'f1%R. P. thereby allowing 31.4-inches of tape to pass over this -disc ina 3 minute period. This reduced rate of tape-travel allows -seconds "forsiren actuation during travelof theuncoded 5.2 inches of 'tape 'from:perforating punch .13! to signaling contacts .38 and 39. Also, thefollowing coded tape allows contacts 38 and --39 'to close -for onesecond :for eachrecorded pulse, with three seconds space between digits:and six @seconds space "between groups ot-digits.

flDisc 74:! has aldiameter :of 12% and is :geared to -disc 32 to rotatein a counterclockwise :direction at a speed of 1 R. P. DiscMhas-adiameter of 2 :inches and is geared to :disc .to rotate in acounterclockwise direction one revolution in three minutes.

The -reception of thenrst pulse of .a :series 101 pulses of proper audiofrequency operates the tuned audio relay 43 to close its contacts. 44-rand 44a. -This completes an A.:C.circuit:to then-erforating coil 45andrelaiy-noillfi. 30135145 10035 in through contacts 41, 48, 49, 50.Contacts 5! and 52 also close to complete A. C. circuit to motor 36.Contacts 53 and 54 are adjusted to open after contacts 41, 48, 49 and 50have closed, thereby opening lead to coil 46 from contact 44 of relay43, preventing shorting of contacts 44 and fla ofrrelay 43iwhen relay46:1ocks in. lDTiVB disc 32: starts to'rotate.causingislacktoiform intape 28 shown by loop 55, thereby closing tape-pressure vcontrolledcontacts 56, 51 which complete an A. C. circuit to motor 40, startingrotation of drive disc .35. Subsequent-pulses continue to operate relay43 and coil and tape 28 is coded by perforating 150001531. The speed *ofrotation of disc 32 being greater :than'ithat of 35 will cause the tapeto .loop at.55 as shown.

-Atthe end of aone-minute period, disc 4| will havennade. one revolutionand cam 58 will open contacts 49 and to de-energize relay 46 andopemcontactsfil :and .52 to stop.motor 36. Disc 35 willcontinue torotate until tapev becomes .taut and-opens contacts 56...and..51tostopmotor 40.

Cam 59 on disc 42 closes siren control contacts i0 and J5 I .for firstl5.seconds .of .rotation. Ibis allows the siren to reach maximum speed,and another 15-.secondsis-required for .it to coast to a stop. By thistime .the perforated portionof the .tape has reachedair-horn controlcontacts 38. .and .39, which then.close=and .opento .audibly sound-thepull-box. number.

,Aiter afone minute period asecondalarmmay be stored, :the first. pulserepeating the operation previously .explainedand .the tape .28 willform.a:loop.55 asshown. .Asaprecaution against jamming, instructions maybe ,placed on-each pull-box, advising .not-to actuate the box for oneminute after thestarting-of .a siren signal warning of .a previouslyreceived alarm.

Operation of radio alarm transmitting, recording and-:signalingsystem:Having described the-construction and operation :of the pull-box audioimpulse =.coding mechanism and the audio .impulseirecording :andsignaling system, references-is, now made to .Fig. :5 for the purposeiof explaining .the operation of the :complete radio alarm .system.

Transmitting unit "The transmitter, audio impulse coding :mechanismgenerally :indicated :at 163, vibrator type platexrpowersupply -'64 :and:6 volt battery are housed in a weather proof aluminum case 62. Bowerfrom the transmitter :is flied to:a;half-wav.e dipole antenna :66l'byrmeans-o'f coaxial cable 161.

Access to the actuating slever I4 is had by opening a'smallauxiliarydoor on thelarge door t5=zof the housing r62. When this leveris depressed as explained :in :connection .with Figs. 1 to .3 inclusive,its cam action places the impulse ceding mechanism .ingoperation.'The'contacts 19.320 close'to complete-a circHitfrom battery-65 to itheitube filaments, and also :to :the input of plate "QDWBILSUDDlYiBA.After a 10.:second trans- .mitter -warm-up period, the. :coding teeth-ondisc l3 of the coding mechanism 63 are :in position toaclose contactsf2,5,-"Z6, thereby completing the plate circuit ofithe audio oscillator,allowing it to generate pulses of a selected audio frequency, which areemployed to,:drive the modulator tube. Radio frequency power, modulatedwith audio pulses designating thezpull-ibox number, is .radiated :Eromthe-antenna. .66.

.A-fterrepeating .the'Pull-Zhox designating signals four times, theicodingzmechanism stops, automatically opening'the battery circuit tofilaments and. plate power supply, and also resetting the actuatinglever for subsequentoperation.

Recording and signalling unit and appear in the output circuit as audiopulses.

If the values of L and C of tuned audio relay 43 are chosen to causecircuit resonance at the audio pulse frequency, the contacts 44 and 44awill close for each pulse received. Closing of contacts 44 and 44acompletes an energizing circuit to the perforating coil 45 and relay 46.Operation of the recording and signalling unit is then as described inexplanation of Fig. 4, causing the siren S to sound for 30 secondsfollowed by operation of the air-horn connected at AI-I to code thenumber of the transmitting pull-box.

While the system as shown employs the transmission and reception ofamplitude modulated radio signals, it will operate equally as well withphase or frequency modulated signals.

As the construction of spring-driven motors such as that employed in thepull-box Fig. l to drive disc [2 and I3 is well known, same is notdescribed herein in detail. This also applies to the details ofconstruction of the crystal controlled transmitter, plate power supply,crystal controlled receiver and other component parts which are of anysuitable construction.-

And, while a preferred embodiment of the invention has been described byway of illustration, it will be understood that many change andmodifications can be made therein without however, departing from theappended claims which define the invention herein set forth.

What is claimed is:

l. A radio transmitter comprising a crystal controlled R. F. oscillator,a R. F. amplifier, an audio oscillator, a modulator adapted to modulatethe R. F. amplifier with single frequency pulsed audio tones, a powersupply, a spring actuated impulse coding mechanism including anactuating lever adapted to be manually moved to release said mechanism,a first contact operated by the movement of said lever for controllingthe application of filament voltage to all tubes and plate voltage tothe R. F. and modu lator tubes of said transmitter, a pulsing memberhaving coding teeth forming part of said mechanism, and a second contactactuated by said teeth for controlling application of plate voltage tothe audio oscillator of said transmitter causing the modulation of theR. F. carrier current with a series of audio pulses corresponding to thenumber and spacing of said coding teeth, said coding mechanism adaptedto maintain the pulse transmission at a selected speed.

2. A radio transmitter as claimed in claim 1 wherein said first contactis timed to closea predetermined time prior tothe operation of saidsecond contact.

3. A radio transmitter as claimed in claim 1 wherein said pulsing membercomprises a disc having teeth extending radially from its periphery,said teeth being disposed in spaced-apart groups, each group comprisingmore than three teeth, the speed of the pulses produced by said pulsingmember being present at 3 per second, with intervals of one secondbetween digits and two seconds between groups of digits.

4. In a radio transmitter of the type described wherein there areinstrumentalities including a transmitting tube necessary to transmit aradio frequency carrier wave modulated with pulsed audio tones of aselected frequency, a motor, a first disc, impulse mechanism including acontact adjacent said disc and adapted to be operated by the rotationthereof, a second disc, a pivoted latch bar associated with said seconddisc and normally restraining both said discs from rotation, a manuallyoperable actuating lever adapted 'to engage said latch bar and move thesame to release said discs for rotation by said motor and a contactactuated by said lever to control the application of filament voltage tothe transmitter tubes.

5. The combination as claimed in claim 4 wherein said second disc has aradial slot into which the free end of said latch projects.

6. In an audio impulse recording and signalling device including a radioreceiver having an output circuit, a tuned audio relay connected to saidoutput circuit for actuation by audio pulses delivered thereto via saidcircuit, contacts controlled by said relay, a perforating mechanismcontrolled by said contacts, a second relay controlled by said contacts,locking contacts on said second relay to hold same closed uponenergization of said relay, first and second motors controlled by saidsecond relay, a tape adapted to be perforated by said perforatingmechanism and moved by said first motor, contacts controlled by saidtape for controlling said second motor, means controlled by said secondmotor for producing a first audible signal, and a second audible signalcontrolled by contacts operated by perforations in said tape.

7. The combination as claimed in claim 6 including means controlled bysaid first motor for opening the circuit to said motor after apredetermined period.

8. The combination as claimed in claim 6 wherein said means controlledby said second motor for producing said first audible signal includescontacts cyclically controlled by said second motor to energize saidsignal during a predetermined operation of said second motor.

9. The combination as claimed in claim 6 including members driven bysaid motors for moving said tape, said motors operating at such speedsthat a loop of said tape is formed therebetween during a predeterminedperiod of operation of said motors.

10. In a system of the class described, a manually operable pulsegenerator including a springoperated contact device adapted to controlthe transmission of audio tone modulated radio signals in a series ofrepetitive groups of impulses, a radio receiver adapted to receive suchsignals and produce corresponding groups of audio pulses, a tuned audiorelay operable by said audio pulses, means controlled by said relay formoving and perforating a tape, means controlled by said tape forterminating the movement thereof, and means controlled by said tape forbroadcasting audible signals corresponding to said audio pulses.

:1-1 -In: a system of the class described, *wherein there .-is a radiotransmitter, 'instr-umentalities necessary -'-to modulate :the radiofrequency =carrier of said transmitter with repetitive groups ofsinglefrequency audio tones, a -mot0r,-a first ,5

disc, pulsing mechanism including contacts eadjacent said disc andadapted to beioperatedby the rotation thereof, a second disc, a pivotedlatch-j-bar associated with said-second disc and normally restrainingboth said discs -f-rom-rotation,-a manually operable actuatinglever'adapted to. engage said latch-bar and move the same to releasesaiddiscs forrotation by said motor,

and :contacts actuated by said lever and said second disc to control theapplication of .filainent voltage 'to the tubes of said radiotransmitter.

PAUL E..FISCHLER.

@REFERENGES CITED Th'e follovving references are of "record in t'h'efile of this paten'tz I UNITED STATES PATENTS

